Ethnicity and biodemographic structure in the Arbëreshe of the province of Cosenza, southern Italy, in the XIX century

Cultural and environmental factors interact in determining the genetic structure of human populations. Bio-demographic investigations of ethnic minorities are able to disentangle the influences that these two components have on the evolution of the genetic structure of a population. The ethnic minority of the Arb?reshe of the province of Cosenza (Calabria, southern Italy) is analyzed in this paper and its bio-demographic structure in the early 1800s is compared with that of neighboring Italian populations. The data derive from surnames recorded in the birth registers of the 19 Arbdreshe municipalities of the province of Cosenza and in 5 non-Arb?reshe municipalities of the same province. Isonymy and repeated pairs of surnames are used to analyze the bio-demographic structure of these populations, while analysis of isonymic relationships is used to investigate the variability between populations. Higher values of marital isonymy and subdivision into subpopulations characterize the Arb?reshe populations with respect to their non-Arb?reshe neighbors. However, the high range of variability of these parameters suggests a strong influence of geographic location on the marriage pattern of each community. At the same time, cultural differences linked to group identity had a strong impact in limiting marriage exchanges between the different ethnic groups living in the province of Cosenza in the early 1800s. In fact, the analysis of isonymic relationships demonstrates that geographic location shaped kinship patterns among the Arbereshe communities, but it also shows that the non-Arb?reshe neighbors formed a clearly separate reproductive cluster.     

ENPP1 affects insulin action and secretion: evidences from in vitro studies

The aim of this study was to deeper investigate the mechanisms through which ENPP1, a negative modulator of insulin receptor (IR) activation, plays a role on insulin signaling, insulin secretion and eventually glucose metabolism. ENPP1 cDNA (carrying either K121 or Q121 variant) was transfected in HepG2 liver-, L6 skeletal muscle- and INS1E beta-cells. Insulin-induced IR-autophosphorylation (HepG2, L6, INS1E), Akt-Ser(473), ERK1/2-Thr(202)/Tyr(204) and GSK3-beta Ser(9) phosphorylation (HepG2, L6), PEPCK mRNA levels (HepG2) and 2-deoxy-D-glucose uptake (L6) was studied. GLUT 4 mRNA (L6), insulin secretion and caspase-3 activation (INS1E) were also investigated. Insulin-induced IR-autophosphorylation was decreased in HepG2-K, L6-K, INS1E-K (20%, 52% and 11% reduction vs. untransfected cells) and twice as much in HepG2-Q, L6-Q, INS1E-Q (44%, 92% and 30%). Similar data were obtained with Akt-Ser(473), ERK1/2-Thr(202)/Tyr(204) and GSK3-beta Ser(9) in HepG2 and L6. Insulin-induced reduction of PEPCK mRNA was progressively lower in untransfected, HepG2-K and HepG2-Q cells (65%, 54%, 23%). Insulin-induced glucose uptake in untransfected L6 (60% increase over basal), was totally abolished in L6-K and L6-Q cells. GLUT 4 mRNA was slightly reduced in L6-K and twice as much in L6-Q (13% and 25% reduction vs. untransfected cells). Glucose-induced insulin secretion was 60% reduced in INS1E-K and almost abolished in INS1E-Q. Serum deficiency activated caspase-3 by two, three and four folds in untransfected INS1E, INS1E-K and INS1E-Q. Glyburide-induced insulin secretion was reduced by 50% in isolated human islets from homozygous QQ donors as compared to those from KK and KQ individuals. Our data clearly indicate that ENPP1, especially when the Q121 variant is operating, affects insulin signaling and glucose metabolism in skeletal muscle- and liver-cells and both function and survival of insulin secreting beta-cells, thus representing a strong pathogenic factor predisposing to insulin resistance, defective insulin secretion and glucose metabolism abnormalities.     

Sorting of GFP Tagged NtSyr1, an ABA Related Syntaxin

Exocytosis molecular mechanisms in plant cells are not fully understood. The full characterization of molecular determinants, such as SNAREs, for the specificity in vesicles delivery to the plasma membrane should shed some light on these mechanisms. Nicotiana tabacum Syntaxin 1 (NtSyr1 or SYP121) is a SNARE protein required for ABA control of ion channels and appears involved in the exocytosis of exogenous markers.NtSyr1 is mainly localized on the plasma membrane, but when over expressed the protein also appears on endomembranes. Since NtSyr1 is a tail-anchored protein inserted into the target membrane post-translationally, it is not clear whether its initial anchoring site is the ER or the plasma membrane.In this study, we investigated the sorting events of NtSyr1 in vivo using its full-length cDNA or its C-terminal domain, fused to a GFP tag and transiently expressed in protoplasts or in the leaves of Nicotiana tabacum cv. SR1. Five chimeras were produced of which two were useful to investigate the protein sorting within the endomembrane system. One (GFP-H3M) had a dominant negative effect on exocytosis; the other one (SP1-GFP) resulted in a slow targeting to the same localization of the full-length chimera (GFP-SP1). The insertion of signal peptides on SP1-GFP further characterized the insertion site for this protein. Our data indicates that NtSyr1 is firstly anchored on ER membrane and then sorted to plasma membrane.Key Words: syntaxins, SNAREs, GFP tagging, exocytosis, secretion, protoplasts, dominant negative mutant     

Salt-induced formation of the A-state of ferricytochrome c--effect of the anion charge on protein structure

Structural information on partially folded forms is important for a deeper understanding of the folding mechanism(s) and the factors affecting protein stabilization. The non-native compact state of equine cytochrome c stabilized by salts in an acidic environment (pH 2.0-2.2), called the A-state, is considered a suitable model for the molten globule of cytochrome c, as it possesses a native-like alpha-helix conformation but a fluctuating tertiary structure. In this article, we extend our knowledge on anion-induced protein stabilization by determining the effect of anions carrying a double negative charge; unlike monovalent anions (which are thought to exert an 'ionic atmosphere' effect on the macromolecule), divalent anions are thought to bind to the protein at specific surface sites. Our data indicate that divalent anions, in comparison to monovalent ions, have a greater tendency to stabilize the native-like M-Fe(III)-H coordinated state of the protein. The possibility that divalent anions may bind to the protein at the same sites previously identified for polyvalent anions was evaluated. To investigate this issue, the behavior of the K88E, K88E/T89K and K13N mutants was investigated. The data obtained indicate that the mutated residues, which contribute to form the binding sites of polyanions, are important for stabilization of the native conformation; the mutants investigated, in fact, all show an increased amount of the misligated H-Fe(III)-H state and, with respect to wild-type cytochrome c, appear to be less sensitive to the presence of the anion. These residues also modulate the conformation of unfolded cytochrome c, influencing its spin state and the coordination to the prosthetic group.     

Network medicine: linking disorders

The molecular events underlying many human hereditary disorders remain to be discovered despite the significant advances made in molecular biology and genetics in the past years. Given the complexity of cellular systems and the interplay between different functional modules, it is becoming increasingly evident that profound insights into human disease cannot be derived by analyzing single genetic defects. The generation of different types of disease interaction networks has recently emerged as a unifying approach that holds the promise of shedding some light on common pathological mechanisms by placing the single disorders into a larger context. In this review, I summarize the rationale behind these disease networks and different ways of constructing them. Finally, I highlight some of the first results that have been obtained by systematically analyzing the intertwined relationships between human disorders because they suggest that the current disease classification does not always sufficiently reflect biologically and medically relevant disease relationships.     

A dysregulated endocannabinoid-eicosanoid network supports pathogenesis in a mouse model of Alzheimer's disease

1. Download : Download full-size image

Highlights? Monoacylglycerol lipase (MAGL) is a major contributor to brain arachidonic acid pools ? MAGL mutation decreases neuroinflammation and amyloid β in Alzheimer's disease mouse ? MAGL blockade recapitulates brain prostaglandin and cytokine-lowering effects ? MAGL inhibitors may be a next-generation strategy for combating Alzheimer's disease     

Fruit and vegetable and fried food consumption and 3-(2-deoxy-β-D-erythro-pentafuranosyl)pyrimido[1,2-α] purin-10(3H)-one deoxyguanosine adduct formation

Diet has been shown to modulate M(1)dG adduct, a biomarker of oxidative stress and lipid peroxidation. Thus, we analysed the association between diet and M(1)dG in 120 controls and 67 Map Ta Phut industrial estate workers in Rayong, Thailand, to evaluate the influence of fruit and vegetables, and fried and charcoal-grilled/barbecued food consumption on M(1)dG. M(1)dG was decreased in controls reporting to consume 14-17 servings/week of fruit and vegetables (mean ratio [MR]= 0.35, CI 0.18-0.69, p< 0.05). Conversely, a non-statistically significant M(1)dG increment was detected in controls consuming 9-18 servings/week of fried food (MR = 1.33, CI 0.88-2.00, p = 0.168). No effect of charcoal-grilled/barbecued food was found. No effect of diet was observed in workers. An association with smoking was observed in controls (MR = 1.88, CI 1.14-3.10, p < 0.05), but not in workers. M(1)dG can induce mutations and/or methylation changes within the promoter regions of cancer-related genes, thus promotion of healthy eating practices should be recommended.     

Non-reducing alkaline solubilization and rapid on-column refolding of recombinant prion protein

Mature prion protein (PrP) is a 208-residue polypeptide that contains a single disulfide bond. We report an alternative method to purify recombinant mouse PrP produced in Escherichia coli. Bacterial inclusion bodies were solubilized in a buffer containing 2 M urea at pH 12.5. The solubilized protein was rapidly purified on a nickel affinity column without a chaotrope gradient, followed by ion-exchange chromatography. The yield and purity of PrP produced by this alternative approach was similar to that obtained using a conventional solubilization and on-column refolding protocol. Recombinant PrP produced using the non-reducing purification protocol is properly folded, as determined by circular dichroism, and a competent substrate for amyloid fibril formation, as determined by Thoflavin-T dye binding assays. In summary, this report describes a rapid method for producing properly folded recombinant PrP without reducing agents or a chaotrope gradient.     

Role of calcium during biosynthesis,secretion and organization of cell-wall polysaccharides

Abstract

The role of calcium during the synthesis, secretion and molecular organization of the primary cell-wall polysaccharides is the topic of this review. With the exception of callose synthase, the in vitro activity of all polysaccharide synthases is not controlled by Ca²⁺ ions. However, changes in the intracellular Ca²⁺ level could control the rate of exocytotic fusion of the secretory vesicles containing cell-wall matrix polysaccharides. In particular, the ability of Ca²⁺ to regulate the fusion of secretory vesicles with the plasma membrane is due to a class of Ca²⁺-dependent phospholipid-binding proteins known as annexins. The ionic interactions between calcium and the negatively charged homogalacturonan domains of the pectins are important not only for the mechanical properties of the wall but also for the gel-properties of these complex biopolymers.